That same year the builder released an upgraded version, the GP9, which was slightly more powerful offering 1,750 hp. Even more successful than the GP7 the latest sold more than 4,000 examples and firmly entrenched EMD as the preeminent builder of that era. The GP9's success also meant the venerable cab unit, which had also witnessed very high sales numbers for EMD through the F7, was on its way out. After 1953 (the final year the F7 was offered) future models saw only a few hundred sales. Interestingly, not all railroads were interested in purchasing new, out-of-the-box GP9s. Most notably was the Great Northern, which embarked on a rebuild program that was very likely the first of its kind at that time. Instead of purchasing brand new locomotives from EMD the railroad requested that parts from its older FTAs and FTBs be reused to reduce costs.
GP5 Production Roster
Rebuilt As Burlington Northern GP28Ms
|GP28M||1517-1522 (Was GP5s 905-906, 908-909, 914-915)||6||1992||Morrison-Knudsen|
By the late 1950s these cab models were nearly 20 years old (the GN
owned 51 A units and 46 B units) and had seen millions of miles of
service. The railroad also had already purchased 56 new GP7s (numbered
600-655) between 1950-1953 and 79 additional GP9s (numbered 656-734)
from 1954-1959. The new "GP5s" began arriving on the railroad during
February of 1958. The units reused various components of the FTs from
generators (the FT carried the General Motors' D12 model while the GP9's
were equipped with the upgraded D12B) to trucks (these were merely reused Blomberg's as the
two models carried the same design). The most notable difference
between the designs was the horsepower rating; the GP5 carried only 1,350 hp some 400 hp less than its counterpart, which was due to
the older generator being rated lower than the newer D12B.
Since these variants were essentially rebuilds they would be classed as GP9Ms in today's lexicon. However, Electro-Motive simply listed them as standard GP9s. In any event, the Great Northern itself came up with the term GP5, which is how the designation came into use. In all, the railroad rostered sixteen examples of these de-rated GP9s, #900-915, and all were delivered by April of 1959. After the GN became part of the much larger Burlington Northern in 1970 the GP5s were renumbered 1350-1365 where they continued in service for over a decade. Finally, BN began retiring the fleet by the mid to late 1980s. However, six remained within the fleet and rebuilt as GP28Ms by Morrison-Knudsen in 1992. Incredibly, these units are still believed to be operating as part of today's BNSF Railway fleet (though no, original GP5s are preserved).
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